TGFB1 and chronic obstructive pulmonary disease: Silibinin, an active constitute of silymarin, could markedly reduce the production of fibrotic mediators in CS + LPS-exposed mice via suppression of TGF-β1/Smad 2/3 signaling (Ko et al., 2017), as well as clearly decrease the pro-inflammatory mediators and airway mucus production expression in CS condensate-stimulated H292 cells and COPD mice model via the inhibition in ERK phosphorylation (Park et al., 2016).